Inkjet printing as an electronics fabrication technology has attracted significant attention over the last decade as a method to fabricate passive and active components. Printing of electronics allows for rapid prototyping, low material wastes, and does not require cleanroom environments. Conventional methods of fabricating multi-layer passive structures such as metal-insulator-metal (MIM) capacitors, require a sequence of photolithography and etching steps which use harsh chemicals and waste a large amount of material in the subtractive process. Inkjet printing, however, is a purely additive and non-contact process meaning it only deposits the required material, and can successively deposit multiple layers of different materials without disturbing the previously deposited layers. This makes the process very attractive for multi-layer printing of RF components.
Up until now, low-frequency passives including resistors, capacitors, and inductors have been demonstrated in the literature with resonant frequencies up to 10 MHz utilizing the inkjet process. These low-frequency passives are deposited in a single plane. Multi-layer printed MIM structures have yet to be demonstrated and optimized for operation at microwave frequencies through several GHz. Printed microwave capacitors on flexible substrates have a wide variety of applications, especially in printed wearable systems which currently require the use of discrete mounted components. Accordingly, there is a desire for systems and methods that address the shortcomings of these conventional techniques. Various embodiments of the present invention address these desires.